This competitive continuation proposal requests a 5-year renewal for our Institutional National Research Service Award (T-32) Research Training: The Science of Child Mental Health Treatment, located at the UCLA Semel Institute. The program is designed to provide transdisciplinary research training to postdoctoral level young investigators in the broad area of child mental health treatment research. Trainees will identify specific areas of childhood mental illness and chose research strategies that advance such research at a variety of levels-treatment mechanisms, efficacy study methodology, and applications. General goals for the trainees will be to obtain a broad background in current issues in child mental health treatment research; and develop skills necessary for transitioning into an independent investigator. This program will continue and expand a nexus for training in issues pertaining to treatment of developmental psychopathologies which does not exist elsewhere in the region. Research training will occur at the translational intersection of disorder- specific areas-child anxiety, ADHD and disruptive disorders, autism spectrum disorders, mood disorders and suicide, and neuropsychiatric disorders-with examination of levels of treatment, such as mechanisms or biomarkers of treatment, efficacy study methods, or application of treatment research. The core training experience will occur within the trainee's own research and in their close interaction with a preceptor. In addition, participation in core didactic coursework and supplementary coursework and experiences will provide broad and specific knowledge in research approaches. The combination of trainees focusing on basic and applied research will broaden research perspectives and prepare trainees for work in collaborative research projects. Based on the initial success and high demand for positions from many qualified applicants, the proposed plan consists of training 7 postdoctoral students per year with medical or doctoral degrees. Postdoctoral trainees will possess clinical training in a discipline relevant to child mental health treatment, or plan to complete such training following the conclusion of the two-year research training period. The program will benefit from the breadth of active treatment research at UCLA and from the supplemental cross-disciplinary training available from a wide variety of departments, programs, research units, and other training activities.